This document discusses different classifications of contracts. It begins by defining express and implied promises or contracts. Express contracts are those made in words, either written or oral, while implied contracts have acceptance or proposals made without words.
The document then covers classifications based on enforceability and validity. It defines valid contracts as those that are enforceable by law if they meet requirements of free consent, lawful consideration, lawful object and are not declared void. Void contracts cease to be enforceable and become void. Voidable contracts are enforceable at the option of one or more parties but not others.